This is a clinical research study to evaluate the effectiveness of low-dose 13-cis retinoic acid in preventing second primary tumors in patients who have been successfully treated for cancer of the head and neck. Head and neck cancer accounts for 5% of all cancers in the USA.Standard treatment for stage III and IV disease is surgery and/or radiotherapy (RT) with the major causes of failure being loco-regional and distant metastases. Standard treatment for stage I and II disease is either surgical excision or RT with the major causes of failure being development of second primary tumors. In 1983, a chemopreventive study of high-dose 13-cis retinoic acid (13-cRA) versus placebo in patients with head and neck squamous cell carcinoma revealed that the 13-cRA treatment significantly reduced the incidence of second primary tumor development. Toxicity in the 13-cRA group was more severe and more often intolerable than in the placebo group. This study will determine whether low-dose 13-cRA is an effective long-term treatment for reducing second primary tumors. The side effects from this medication will also be evaluated.